DCT

2:21-cv-15782

Tolmar Therap Inc v. Foresee Pharma Co Ltd

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:21-cv-15782, D.N.J., 04/04/2022
  • Venue Allegations: Venue is alleged based on Defendant Foresee’s use of a New Jersey-based agent to prepare and file its New Drug Application, and on both Defendants’ alleged marketing and sales activities within the district.
  • Core Dispute: Plaintiff alleges that Defendants’ Camcevi® injectable emulsion for treating prostate cancer infringes a patent related to a specific type of sustained-release polymer formulation.
  • Technical Context: The technology concerns biodegradable polymers used in drug-delivery systems that provide controlled, long-term release of a medicament after injection, a common approach for hormone-based cancer therapies.
  • Key Procedural History: The action stems from Defendants’ submission of New Drug Application (NDA) No. 211488 to the FDA. The complaint notes that Plaintiff sent a notice letter to Defendant Foresee on June 16, 2021. It also alleges that Foresee was aware of the patent-in-suit as early as April 5, 2019, when it was cited in an Information Disclosure Statement during the prosecution of a Foresee patent.

Case Timeline

Date Event
2000-11-13 U.S. Patent No. 8,470,359 Priority Date
2013-06-25 U.S. Patent No. 8,470,359 Issue Date
2019-04-05 Foresee allegedly cites '359 Patent in an Information Disclosure Statement
2020-07-27 Foresee submits New Drug Application (NDA) No. 211488
2021-05-25 FDA approves NDA No. 211488
2021-06-16 Tolmar sends notice letter to Foresee
2022-01-01 Accord becomes Applicant Holder for NDA No. 211488 (approx. date)
2022-03-31 Accord announces U.S. launch of Camcevi Product
2022-04-04 Complaint Filing Date

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

U.S. Patent No. 8,470,359 - Sustained Release Polymer

  • Patent Identification: U.S. Patent No. 8,470,359, "Sustained Release Polymer," issued June 25, 2013.

The Invention Explained

  • Problem Addressed: The patent describes the need for improved biodegradable polymers for controlled drug release, particularly for treating prostate cancer. A key challenge with existing polyester-based delivery systems is that acidic functional groups on the polymer can cause "auto-catalytic degradation," which can negatively affect the drug release profile over long periods. ('359 Patent, col. 10:3-8).
  • The Patented Solution: The invention is a novel biodegradable polymer with a specific structure: two polymer segments (like poly(lactide-glycolide)) are covalently bonded to a central "alkanediol core." This design results in a polymer that is terminated at both ends with hydroxyl (-OH) groups and has "substantially no titratable carboxylic acid groups." ('359 Patent, col. 2:47-62; col. 3:28-34). This "chemical neutrality" is described as an "outstanding advantage" that avoids the auto-catalytic degradation problem and enables a longer, more stable drug release. ('359 Patent, col. 10:3-8).
  • Technical Importance: This polymer structure is stated to enable sustained drug release over surprisingly long periods, such as 120 or 180 days, which can reduce the frequency of injections for patients. ('359 Patent, col. 4:1-9).

Key Claims at a Glance

  • The complaint asserts infringement of independent claim 1.
  • The essential elements of Claim 1 are:
    • A flowable composition for a controlled release formulation comprising:
    • an organic solvent,
    • a medicament,
    • and a polymer of the specific formula: HO—(P)—C(=O)O—Rª—O(O=)C—(P)—OH,
    • wherein Rª is an "alkane diradical comprising about 4 to about 8 carbons" and is the "residue of an alkane diol,"
    • and P is a polymeric segment of specific repeating lactide and/or glycolide units,
    • and wherein the polymer has specific properties, including being "substantially insoluble," having "substantially no titratable carboxylic acid groups," a specific molecular weight range (10-50 kD), and being a solid at ambient temperature.
  • The complaint reserves the right to assert dependent claims 4, 6, 8, and 11-16. (Compl. ¶59).

III. The Accused Instrumentality

Product Identification

  • The accused product is Defendants' Camcevi® 42mg (leuprolide) injectable emulsion. (Compl. ¶1).

Functionality and Market Context

  • Camcevi is a sterile, pre-filled syringe product for subcutaneous injection, intended for the palliative treatment of advanced prostate cancer. (Compl. ¶¶ 29, 33). It is designed to deliver the active medicament, leuprolide, over a six-month period. (Compl. ¶33). The formulation contains leuprolide mesylate, a poly(D, L-lactide) polymer, and the organic solvent N-methyl-2-pyrrolidone. (Compl. ¶33). The complaint alleges the poly(D, L-lactide) polymer in Camcevi is synthesized using a "lauryl alcohol initiator (C12H25OH)," which results in a polymer structure different from that literally recited in the asserted claim. (Compl. ¶37). The complaint reproduces the chemical structure of leuprolide mesylate from the accused product's label, illustrating the active medicament. (Compl. ¶33).

IV. Analysis of Infringement Allegations

The complaint's infringement theory for several key limitations of Claim 1 is based entirely on the doctrine of equivalents, not literal infringement.

'359 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
a polymer of Formula HO—(P)—C(=O)O—Rª—O(O=)C—(P)—OH The Camcevi polymer allegedly has the formula Rª—O(O=)C—(P)—OH and is asserted to be equivalent. The complaint argues the difference in structure is insubstantial because both polymers preserve the "outstanding advantage" of chemical neutrality by lacking acidic end-groups. (DOE allegation) ¶¶ 38-43 col. 11:4-9
Rª is an alkane diradical comprising about 4 to about 8 carbons and is a residue of an alkane diol The Camcevi polymer is allegedly initiated with lauryl alcohol, resulting in an Rª group of C12H25 derived from a mono-alcohol, not a diol. This is asserted to be an insubstantial difference because the initiator group is a small part of the polymer's weight. (DOE allegation) ¶¶ 44-48 col. 11:10-14
P is a polymeric segment of repeating units of...co(lactide-glycolide)...moieties The Camcevi polymer includes a polymeric segment of repeating units (P) of lactide. ¶49 col. 11:15-18
the polymer has substantially no titratable carboxylic acid groups The Camcevi polymer allegedly contains a hydroxyl end-group and an ester end-group, and thus has substantially no titratable carboxylic acid groups. ¶51 col. 11:21-22
the polymer has a weight average molecular weight from about 10 kD to about 50 kD On information and belief, the Camcevi polymer has an average molecular weight within the claimed range. ¶52 col. 11:23-25
the organic solvent is a polar, aprotic organic solvent having at least some water solubility The Camcevi product uses N-methyl-2-pyrrolidone, which is alleged to be a polar, aprotic solvent with some water solubility. ¶54 col. 12:1-4
  • Identified Points of Contention:
    • Scope Questions (Doctrine of Equivalents): The case appears to hinge on the doctrine of equivalents. A primary question is whether the accused single-chain polymer (allegedly Rª—O(O=)C—(P)—OH) can be found equivalent to the claimed two-chain polymer (HO—(P)—...—(P)—OH). The plaintiff’s theory is that the "way" and "result" are the same because both designs achieve chemical neutrality.
    • Technical Questions: A key technical dispute will be whether a polymer initiated with a 12-carbon mono-alcohol (lauryl alcohol) is equivalent to one initiated with a 4-to-8 carbon diol. This raises questions not only about the polymer's core structure (one-armed vs. two-armed) but also about the chemical and physical differences arising from the initiator's size and functionality.

V. Key Claim Terms for Construction

  • The Term: "a polymer of Formula HO—(P)—C(=O)O—Rª—O(O=)C—(P)—OH"

  • Context and Importance: This term defines the core architecture of the invention. Its construction will be dispositive for infringement, as the accused product allegedly uses a structurally different, single-chain polymer. The dispute will focus on whether this formula is a strict structural limitation or a representation of a broader concept (e.g., hydroxyl-terminated neutral polymers).

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The patent repeatedly emphasizes the functional result of the structure—its chemical neutrality and lack of acidic groups—as the "outstanding advantage." A party could argue this functional goal is paramount and the specific two-chain structure is merely a preferred embodiment for achieving it. ('359 Patent, col. 10:3-8).
    • Evidence for a Narrower Interpretation: The specification consistently describes the invention as having two polymer segments bonded to a central "alkanediol core." ('359 Patent, col. 2:47-54). The claim language itself is a precise chemical formula depicting a symmetric, two-chain structure. A party could argue this explicit recitation limits the claim to this specific architecture.

  • The Term: "Rª is an alkane diradical comprising about 4 to about 8 carbons and is a residue of an alkane diol"

  • Context and Importance: This term is critical because the accused product allegedly uses an initiator that is a 12-carbon mono-alcohol, falling outside both the carbon count and the "diol" requirement. Practitioners may focus on this term because the differences are stark and test the limits of the doctrine of equivalents.

  • Intrinsic Evidence for Interpretation:

    • Evidence for a Broader Interpretation: The complaint argues the difference is "insubstantial" from a functional perspective within the context of a large polymer. (Compl. ¶46). A party might argue "about 8" could be stretched to 12 if the initiator's function is merely to start a chain reaction without creating acidic groups.
    • Evidence for a Narrower Interpretation: The patent provides a specific numeric range (4 to 8) and a specific chemical class ("alkane diol"). The specification lists specific examples of "a,w-diols" like 1,6-hexanediol, all of which fit the claim language precisely. ('359 Patent, col. 8:10-15). This specificity suggests the patentee deliberately claimed a narrow group of initiators.

VI. Other Allegations

  • Indirect Infringement: The complaint alleges that Defendants induce infringement by providing Camcevi with labeling and instructions that direct medical professionals to administer the product, thereby performing the claimed method of use. (Compl. ¶¶ 75, 101). It further alleges contributory infringement, stating Camcevi is especially adapted for this infringing use and has no substantial non-infringing uses. (Compl. ¶¶ 76, 102).
  • Willful Infringement: Willfulness is alleged based on Defendants' purported knowledge of the '359 Patent. The complaint cites multiple grounds for this knowledge: a notice letter sent by Plaintiff, the filing of the lawsuit itself, and, notably, Defendant Foresee’s citation of the '359 Patent in an Information Disclosure Statement filed with the USPTO in 2019 during prosecution of its own patent. (Compl. ¶¶ 63, 78, 89).

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

  • A core issue will be one of structural equivalence: can a polymer formed with a single polymer chain initiated by a mono-alcohol be legally equivalent to the claimed polymer defined by a two-chain architecture initiated by a central diol? The analysis will likely focus on whether achieving the same result (chemical neutrality) is sufficient to overcome the significant differences in the "way" the polymer is constructed.
  • The case will also present a question of definitional boundaries: do the explicit limitations of an "alkane diol" and a carbon count of "about 4 to about 8" create a clear line that the doctrine of equivalents cannot cross to cover a 12-carbon mono-alcohol initiator? The court's decision may turn on whether this alternative was foreseeable and should have been claimed by the patentee.